Operating Systems (CSE) Test-1

one of the true problems with priority scheduling is

• Aging

• Starvation

• Decreases in throughput

• Context Switch overhead

Answer explanation

One of the true problems with priority scheduling is starvation, where lower-priority processes may never get executed if higher-priority processes keep arriving, leading to indefinite postponement.

_algorithm executes the shortest job first that has entered the queue of jobs.

• FIFO

• SJF

• Round Robin

• LIFO

Answer explanation

The SJF (Shortest Job First) algorithm prioritizes jobs based on their execution time, executing the shortest job in the queue first. This distinguishes it from FIFO, Round Robin, and LIFO scheduling methods.

What is a long-term Schedular?

• it selects which process has to be brought into the ready queue

• it selects which process has to be executed next and allocates cpu

• it selects which process to remove from memory by swapping

• it selects which process has to be brought into the blocked process

Answer explanation

A long-term scheduler is responsible for selecting processes from the job pool and bringing them into the ready queue, making the correct choice: 'it selects which process has to be brought into the ready queue'.

The schedular which determines when processes are to be suspended and removed

• short-term schedular

• long-term schedular

• medium-term schedular

• job schedular

Answer explanation

The medium-term schedular is responsible for suspending and resuming processes, managing their presence in memory. This distinguishes it from short-term and long-term schedulers, which handle CPU scheduling and job admission, respectively.

which of the following technique is used for increasing the priority of a waiting process

• Revocation

• Aging

• Relocation

• Swapping

Answer explanation

Aging is a technique used to gradually increase the priority of waiting processes over time, preventing starvation. This ensures that processes waiting for a long time eventually get CPU time, making it the correct choice.

context switching never takes place in

• Round Robin scheduling

• preemptive scheduling

• FCFS scheduling

• premptive shortest job first scheduling

Answer explanation

In FCFS (First-Come, First-Served) scheduling, processes are executed in the order they arrive without preemption. This means context switching does not occur until the current process finishes, making it the correct choice.

which one of the following cpu scheduling algorithm leads to starvation problem.

• FIFO

• Round Robin

• SJF

• preemptive

Answer explanation

The SJF (Shortest Job First) scheduling algorithm can lead to starvation because shorter processes may continuously preempt longer ones, preventing them from executing. This can indefinitely delay longer jobs, causing starvation.

the process that are residing in main memory and are ready and waiting to execute are kept on a list called

• job Queue

• Ready queue

• Execution queue

• process queue

Answer explanation

The correct answer is 'Ready queue' because it specifically refers to the list of processes in main memory that are ready and waiting to execute. Other options do not accurately describe this state.

In unix traditional scheduling_

• a cpu-bound process is given higher priority than an I/O bound process

• an I/O bound process is given higher priority than a cpu -bound process

• both cpu-bound & I/O-bound process are given equal priority

• it depends on the current load on the system

Answer explanation

In traditional Unix scheduling, CPU-bound processes are prioritized over I/O-bound processes. This is because CPU-bound processes require more CPU time, while I/O-bound processes spend more time waiting for I/O operations.

process are executed on the sequence they arrive if_rule sequence the jobs

• Earliest due data

• First come First served

• Slack time remaining

• Critical Ratio

Answer explanation

The correct choice is 'First come First served' because it describes a scheduling method where processes are executed in the order they arrive, without prioritization based on other factors.